Apparatus and method for adjusting pH of solution

ABSTRACT

A pH adjusting apparatus includes an electrolytic chip receiving a solution, an electrolytic chip loading station receiving the electrolytic chip, an input unit inputting electrolysis conditions, a control unit receiving the electrolysis conditions and controlling electrolysis performed in the electrolytic chip, and a display unit displaying the electrolysis conditions and a progress of the electrolysis. Thus, the pH of a solution can be adjusted easily and accurately, by precisely controlling a constant current, a constant voltage, and current and voltage application times, thereby enabling useful application in various biological assays such as cell lysis. Furthermore, the pH adjusting apparatus has small size and weight and can be operated for a long time after charging once due to low power consumption.

This application claims priority to Korean Patent Application No.10-2006-0001395, filed on Jan. 5, 2006 and all the benefits accruingtherefrom under 35 U.S.C. §119, and the contents of which in itsentirety are herein incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a pH adjusting apparatus and a methodof adjusting the pH of a fluid using the same. More particularly, thepresent invention relates to a pH adjusting apparatus for adjusting thepH of a solution accurately and easily, and a method of adjusting the pHof a solution using the pH adjusting apparatus.

2. Description of the Related Art

Generally, molecular diagnosis of specific pathogenic species consistsof four steps: cell lysis, DNA separation, DNA amplification, and DNAdetection.

Efficient extraction of DNAs from cells is needed for many applicationsand essential for molecular diagnosis, in particular, isolation andquantification of pathogenic species. Generally, molecular diagnosisinvolves DNA amplification after DNA extraction. Examples of DNAamplification are polymerase chain reaction (“PCR”) amplification,ligase chain reaction (“LCR”) amplification, stranded-displacementamplification, nucleic acid-based amplification, repair chain reaction(“RCR”) amplification, helicase-dependent amplification, Qβ replicaseamplification, or ligation activated transcription (“LAT”)amplification.

DNA separation from cells is performed using a material capable ofbinding with DNA. A material that can be used for DNA separation may besilica, glass fiber, an anion exchange resin, or a magnetic bead.Generally, cell lysis can be performed using a mechanical method, achemical method, a thermal method, an electrical method, an ultrasonicmethod, or a microwave method.

In various biological assays including molecular diagnosis of specificpathogenic species, individual steps may be performed at different pHvalues.

Conventionally, pH adjustment in biological assays is achieved by addingor removing a pH-adjusting solution, e.g., an acidic solution, a basicsolution, a neutral solution, or a buffer solution, to or from a samplesolution. However, the addition or removal of the pH-adjusting solutionrequires a separate apparatus and process and causes the dilution of thesample solution.

Such an additional process and apparatus for the addition or removal ofthe pH-adjusting solution may seriously affect micro-volume biologicalsample assays, and the dilution of the sample solution may adverselyaffect acquisition or amplification of desired samples. Furthermore, theadded pH-adjusting solution may act as an inhibitor in subsequentbiological assays. In this case, it is necessary to remove thepH-adjusting solution after use.

In biological assays, an electrolysis method is used as another methodfor adjusting the pH of a solution. For example, the pH of a solutioncan be adjusted using H⁺ and OH⁻ ions respectively generated from ananode and a cathode by electrolysis of water. In the pH adjustmentmethod using electrolysis, a current difference may be caused by a saltor cell concentration variation between samples or a resistance changedue to gas generation. Thus, in the electrolysis method, it is importantto constantly maintain a current, since current is the major factor forpH adjustment.

However, a pH adjusting apparatus using constant current electrolysishas not yet been reported. Furthermore, the use of a constantcurrent-generating condenser increases the size and weight of a pHadjusting apparatus, thereby making it difficult to make the apparatusportable.

BRIEF SUMMARY OF THE INVENTION

The present invention provides an apparatus for adjusting the pH of asolution accurately and easily.

The present invention also provides a method of adjusting the pH of asolution using the apparatus.

According to exemplary embodiments of the present invention, there isprovided a pH adjusting apparatus including an electrolytic chip whichreceives a solution whose pH is to be adjusted, an electrolytic chiploading station which receives the electrolytic chip, an input unitwhich inputs electrolysis conditions, a control unit which receives theelectrolysis conditions and controls electrolysis performed in theelectrolytic chip, and a display unit which displays the electrolysisconditions and a process of the electrolysis.

The electrolytic chip may include a chamber that receives the solutionwhose pH is to be adjusted, a cathode disposed at a side of the chamber,and an anode disposed at an opposite side of the chamber. Theelectrolytic chip may further include an ion-exchange material, and theion-exchange material may divide the chamber into a cathode chamberincluding the cathode and an anode chamber including the anode.

The electrolytic chip loading station may include an electrolytic chipsupport that supports the electrolytic chip, an electrode contactterminal that contacts the cathode and the anode of the electrolyticchip and includes a spring pad, and a cover that covers the loadedelectrolytic chip. The electrode contact terminal may be formed on aninside of the cover or on the electrolytic chip support.

The electrolysis conditions may include a current applied to theelectrolytic chip, a voltage applied to the electrolytic chip, a currentapplication time, or a voltage application time, and may include aconstant current applied to the electrolytic chip and a constant currentapplication time.

The pH adjusting apparatus may further include a voltage measurementunit that measures a voltage applied to the electrolytic chip andtransmits measured voltage to the control unit, and a currentmeasurement unit that measures a current applied to the electrolyticchip and transmits measured current to the control unit.

The pH adjusting apparatus may further include an interface connected toa peripheral computer, a memory device that stores information, a powersupply unit, and a power control unit that converts an applied power todifferent powers and supplies the different powers to the electrolyticchip, the control unit, and the display unit.

The input part may include a first button, a second button, and a thirdbutton, and pressing the first button may select between a currentsetting menu, a time setting menu, and a voltage setting menu, pressingthe second button may increase a value of current, time, or voltage, andpressing the third button may decrease a value of current, time, orvoltage.

The pH adjusting apparatus may be sized to fit within an average adulthuman hand.

According to other exemplary embodiments of the present invention, amethod of adjusting a pH of a solution using the above-described pHadjusting apparatus may include (a) supplying a solution including anion having a lower or higher standard oxidation potential than waterinto the anode chamber of the electrolytic chip and supplying a solutionincluding an ion having a lower standard reduction potential than waterinto the cathode chamber of the electrolytic chip, (b) loading theelectrolytic chip on the electrolytic chip loading station, (c)inputting electrolysis conditions; and (d) performing electrolysis inthe anode chamber and the cathode chamber by passing a current throughthe anode and the cathode of the electrolytic chip according to theelectrolysis conditions so that the solution supplied into the anodechamber or the solution supplied into the cathode chamber is adjusted tohave an adjusted pH at a predetermined pH value.

Supplying the solution into the cathode chamber may include supplying acell or a virus, and cell or virus lysis may occur at the adjusted pH ofthe solution. Supplying the solution into the cathode chamber mayinclude supplying one of saliva, urine, blood, serum, and a cellculture.

Inputting the electrolysis conditions may include inputting a currentapplied to the electrolytic chip, a voltage applied to the electrolyticchip, a current application time, or a voltage application time, and mayinclude inputting a constant current to the electrolytic chip and aconstant current application time.

According to still other exemplary embodiments of the present invention,a pH adjusting apparatus includes an electrolytic chip receiving asolution whose pH is to be adjusted, the electrolytic chip including achamber which receives the solution whose pH is to be adjusted, acathode disposed at a side of the chamber, an anode disposed at anopposite side of the chamber, and an ion-exchange material dividing thechamber into a cathode chamber having the cathode and an anode chamberhaving the anode, wherein the cathode and the anode of the electrolyticchip contact a contact terminal of the pH adjusting apparatus andreceive current or voltage through the contact terminal.

The anode may be ladder-shaped and the ion-exchange material may be anion-exchange membrane, and the electrolytic chip may further include ananode support formed between the anode and the ion-exchange membrane anda pillar structure formed between the cathode and the ion-exchangemembrane, the pillar structure and the anode supporting the ion-exchangemembrane there between.

According to the pH adjusting apparatus and method of the presentinvention, the pH of a solution can be adjusted easily and accurately,regardless of a gas generated during electrolysis, a salt concentrationin a sample, or a cytosolic salt concentration variation during celllysis, by precisely controlling a constant current, a constant voltage,and current and voltage application times, thereby enabling usefulapplication of the pH adjusting apparatus and method of the presentinvention in various biological assays such as cell lysis. Furthermore,the pH adjusting apparatus of the present invention is easy to carry dueto small size and weight and can be operated for a long time aftercharging once due to low power consumption.

The pH adjusting apparatus of the present invention can adjust the pH ofa solution easily and accurately using constant current electrolysis.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of the present inventionwill become more apparent by describing in detail exemplary embodimentsthereof with reference to the attached drawings in which:

FIG. 1 is a schematic diagram illustrating an exemplary embodiment of apH adjusting apparatus according to the present invention;

FIG. 2 is a sectional view illustrating an exemplary embodiment of anelectrolytic chip of an exemplary pH adjusting apparatus according tothe present invention;

FIG. 3A is a transmitted, plan view illustrating another exemplaryembodiment of an electrolytic chip of an exemplary pH adjustingapparatus according to the present invention, FIG. 3B is a sectionalview of the exemplary electrolytic chip of FIG. 3A, and FIG. 3C is a topimage of the exemplary electrolytic chip of FIG. 3A;

FIG. 4A is a sectional view illustrating still another exemplaryembodiment of an electrolytic chip of an exemplary pH adjustingapparatus according to the present invention, FIG. 4B is a plan view ofthe exemplary electrolytic chip of FIG. 4A, and FIG. 4C is a top imageof the exemplary electrolytic chip of FIG. 4A;

FIGS. 5A through 5D are sectional views illustrating various exemplaryembodiments of an electrolytic chip loading station of an exemplary pHadjusting apparatus according to the present invention;

FIG. 6A is a perspective view illustrating an exemplary embodiment of apH adjusting apparatus according to the present invention, FIG. 6B is afront view of the exemplary pH adjusting apparatus of FIG. 6A, FIG. 6Cis a top view of the exemplary pH adjusting apparatus of FIG. 6A, FIG.6D is a rear view of the exemplary pH adjusting apparatus of FIG. 6A,FIG. 6E is a front image of the exemplary pH adjusting apparatus of FIG.6A, and FIG. 6F is an image showing a state where an exemplaryelectrolytic chip loading station is uncovered;

FIG. 7A is an exploded perspective view illustrating an exemplaryembodiment of a pH adjusting apparatus according to the presentinvention, FIG. 7B is an image of an exemplary display unit of theexemplary pH adjusting apparatus of FIG. 7A, FIG. 7C is a front image ofan exemplary printed circuit board (“PCB”) of the exemplary pH adjustingapparatus of FIG. 7A, and FIG. 7D is a rear image of the exemplary PCBof the exemplary pH adjusting apparatus of FIG. 7A; and

FIG. 8A is a flow diagram illustrating an exemplary embodiment of aprogram executed in an exemplary control unit of an exemplary pHadjusting apparatus according to the present invention, FIG. 8B is aflow diagram illustrating an exemplary embodiment of menu/voltagecontrol, FIG. 8C is a flow diagram illustrating an exemplary embodimentof AD conversion/current control, and FIG. 8D is a flow diagramillustrating an exemplary embodiment of data communication with aperipheral computer via an interface.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will now be described more fully with reference tothe accompanying drawings, in which exemplary embodiments of theinvention are shown. This invention may, however, be embodied in manydifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art. Likereference numerals refer to like elements throughout.

It will be understood that when an element is referred to as being “on”another element, it can be directly on the other element or interveningelements may be present there between. In contrast, when an element isreferred to as being “directly on” another element, there are nointervening elements present. As used herein, the term “and/or” includesany and all combinations of one or more of the associated listed items.

It will be understood that, although the terms first, second, third etc.may be used herein to describe various elements, components, regions,layers and/or sections, these elements, components, regions, layersand/or sections should not be limited by these terms. These terms areonly used to distinguish one element, component, region, layer orsection from another element, component, region, layer or section. Thus,a first element, component, region, layer or section discussed belowcould be termed a second element, component, region, layer or sectionwithout departing from the teachings of the present invention.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” or “includes” and/or “including” when used in thisspecification, specify the presence of stated features, regions,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,regions, integers, steps, operations, elements, components, and/orgroups thereof.

Spatially relative terms, such as “beneath”, “below”, “lower”, “above”,“upper” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” or “beneath” otherelements or features would then be oriented “above” the other elementsor features. Thus, the exemplary term “below” can encompass both anorientation of above and below. The device may be otherwise oriented(rotated 90 degrees or at other orientations) and the spatially relativedescriptors used herein interpreted accordingly.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this invention belongs. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art and thepresent disclosure, and will not be interpreted in an idealized oroverly formal sense unless expressly so defined herein.

Embodiments of the present invention are described herein with referenceto cross section illustrations that are schematic illustrations ofidealized embodiments of the present invention. As such, variations fromthe shapes of the illustrations as a result, for example, ofmanufacturing techniques and/or tolerances, are to be expected. Thus,embodiments of the present invention should not be construed as limitedto the particular shapes of regions illustrated herein but are toinclude deviations in shapes that result, for example, frommanufacturing. For example, a region illustrated or described as flatmay, typically, have rough and/or nonlinear features. Moreover, sharpangles that are illustrated may be rounded. Thus, the regionsillustrated in the figures are schematic in nature and their shapes arenot intended to illustrate the precise shape of a region and are notintended to limit the scope of the present invention.

Hereinafter, the present invention will be described in detail withreference to the accompanying drawings.

The present invention provides a pH adjusting apparatus capable ofadjusting the pH of a solution accurately and easily using constantcurrent electrolysis.

FIG. 1 is a schematic diagram illustrating an exemplary embodiment of apH adjusting apparatus according to the present invention.

Referring to FIG. 1, the pH adjusting apparatus includes an electrolyticchip 10 for receiving a solution whose pH is to be adjusted, anelectrolytic chip loading station 11 for receiving the electrolytic chip10, an input unit 12 for inputting electrolysis conditions, a controlunit 13 for receiving the electrolysis conditions and controllingelectrolysis performed in the electrolytic chip 10 according to theelectrolysis conditions, and a display unit 14 for displaying theelectrolysis conditions and the progress of the electrolysis.

As will be further described below, the electrolytic chip 10 may includea chamber for receiving the solution whose pH is to be adjusted, acathode disposed at a side of the chamber, and an anode disposed at anopposite side of the chamber.

The electrolytic chip 10 may further include an ion-exchange material,and the ion-exchange material may divide the chamber into a cathodechamber including the cathode and an anode chamber including the anode.

In the exemplary embodiments of the present invention, the ion-exchangematerial allows the passage of a current, but blocks the passage of ionsor gases generated by electrolysis in each of the cathode chamber andthe anode chamber. Preferably, the ion-exchange material allows thepassage of a current but blocks the passage of hydrogen ions andhydroxide ions. The ion-exchange material may be a cationic exchangefilm or an anionic exchange film.

FIG. 2 is a sectional view illustrating an exemplary embodiment of anelectrolytic chip of an exemplary pH adjusting apparatus according tothe present invention.

Referring to FIG. 2, the electrolytic chip, usable as the electrolyticchip 10 in FIG. 1, includes an ion-exchange membrane 17 and a chamber.The ion-exchange membrane 17 divides the chamber into two parts: acathode chamber 18 including a cathode 15 and an anode chamber 19including an anode 16. The cathode 15 is disposed on one side of thechamber, while the anode 16 is disposed on an opposite side of thechamber.

FIG. 3A is a transmitted, plan view illustrating another exemplaryembodiment of an electrolytic chip of an exemplary pH adjustingapparatus according to the present invention, FIG. 3B is a sectionalview of the exemplary electrolytic chip of FIG. 3A, and FIG. 3C is a topimage of the exemplary electrolytic chip of FIG. 3A.

Referring to FIGS. 3A through 3C, the electrolytic chip, usable as theelectrolytic chip 10 in FIG. 1, includes an ion-exchange material 17, acathode chamber 18, a boundary of which is formed with a surface of theion-exchange material 17, and wherein a cathode 15 is disposed in thecathode chamber 18 along edges of the boundary with the surface of theion-exchange material 17, and an anode chamber 19, a boundary of whichis formed with a surface of the ion-exchange material 17, and wherein ananode 16 is disposed in the anode chamber 19 along edges of the boundarywith the surface of the ion-exchange material 17. The cathode chamber 18and the anode chamber 19 are partitioned by a nonconductor 20. Thecathode chamber 18 and the anode chamber 19 are surrounded by asubstrate 21, and the substrate 21 may further include an ion-exchangematerial inlet 22.

The ion-exchange material 17 may have characteristics such that it canbe used to form a film by cross-linking reaction. The use of such anion-exchange material ensures easy fabrication of a micro-scaleelectrolytic chip.

More preferably, the ion-exchange material 17 may be a materialdisclosed in U.S. patent application Ser. No. 11/453,116, filed on Jun.14, 2006 and entitled “Ion-Exchangeable Mixture and Method of Producingthe Same”, filed by the present applicant, the disclosure of which isincorporated herein in its entirety by reference.

FIG. 4A is a sectional view illustrating still another exemplaryembodiment of an electrolytic chip of an exemplary pH adjustingapparatus according to the present invention, FIG. 4B is a plan view ofthe exemplary electrolytic chip of FIG. 4A, and FIG. 4C is a top imageof the exemplary electrolytic chip of FIG. 4A.

Referring to FIGS. 4A through 4C, the electrolytic chip, usable as theelectrolytic chip 10 in FIG. 1, includes an ion-exchange membrane 17, ananode chamber 19, a boundary of which is formed with a surface of theion-exchange membrane 17, including a ladder-shaped anode 16 and ananode support 23, and a cathode chamber 18, a boundary of which isformed with an opposite surface of the ion-exchange membrane 17,including a cathode 15. The elements of the electrolytic chip may beenclosed within first and second substrates 21 a and 21 b. Theladder-shaped anode 16 is disposed on a surface of the anode support 23,and the ion-exchange membrane 17 is disposed on the opposite surface ofthe anode support 23 to support the ion-exchange membrane 17. The anodesupport 23 has openings defined by the ladder shape of the anode 16. Apillar structure 24 is disposed at a surface of the cathode chamber 18that is opposite to a surface of the cathode chamber 18 contacting withthe ion-exchange membrane 17. The pillar structure 24 contacts with theion-exchange membrane 17 to support the ion-exchange membrane 17. Thus,the anode support 23 contacts one side of the ion-exchange membrane 17,and the pillar structure 24 contacts an opposite side of theion-exchange membrane 17. The pillar structure 24 facilitates theadsorption of biomolecules. The electrolyte chip may also include aninlet 22 a and an outlet 22 b of the cathode chamber 18, and a contactterminal connecting hole 25.

In the electrolytic chip shown in FIGS. 4A through 4C, the ion-exchangemembrane 17 is supported by the anode support 23 and the pillarstructure 24, thereby preventing the swelling of the ion-exchangemembrane 17 and thus minimizing a volume change of the anode chamber 19and the cathode chamber 18. Furthermore, uniform distribution of theladder-shaped anode 16 facilitates a current flow, thereby ensuringefficient adjustment of pH.

In the electrolytic chip shown in FIGS. 4A through 4C, the cathode 15may include a metal capable of adsorbing a hydrogen gas and the anode 16may include a metal that has a higher standard oxidation potential thanwater and does not react with water to prevent the generation of gasbubbles in the anode chamber 19 and the cathode chamber 18. For example,the cathode 15 may be made of, for example, palladium (Pd), and theanode 16 may be made of a metal selected from a group including, forexample, copper (Cu), lead (Pb), silver (Ag), chromium (Cr), titanium(Ti), nickel (Ni), zinc (Zn), iron (Fe), and tin (Sn).

FIGS. 5A through 5D are sectional views illustrating various exemplaryembodiments of an electrolytic chip loading station of an exemplary pHadjusting apparatus according to the present invention.

Referring to FIGS. 5A through 5D, electrolytic chip loading stations 11,usable in the pH adjusting apparatus shown in FIG. 1, include anelectrolytic chip support 26 for supporting an electrolytic chip 10, anelectrode contact terminal 28 contacting with a cathode (not shown) andan anode (not shown) of the electrolytic chip 10 and including a springpad 27, and a cover 29 for covering the electrolytic chip 10 loaded onthe electrolytic chip support 26. For example, the electrolytic chip 10may be any of the above-described exemplary embodiments of anelectrolytic chip.

Referring to the electrolytic chip loading stations 11 shown in FIGS. 5Aand 5B, the electrode contact terminal 28 is disposed on theelectrolytic chip support 26, and the spring pad 27 is disposed withinthe electrolytic chip support 26. The electrolytic chip loading station11 shown in FIG. 5A is different from that shown in FIG. 5B with respectto the position of a pivot shaft of the cover 29. That is, in FIG. 5A,the pivot shaft of the cover 29 is positioned on a side of theelectrolytic chip support 26 opposite the electrode contact terminal 28,such that the electrolytic chip 10 is disposed between the pivot shaftand the electrode contact terminal 28 when the cover 29 is closed. InFIG. 5B, the pivot shaft of the cover 29 is positioned on a same side ofthe electrolytic chip support 26 as the electrode contact terminal 28,such that the electrolytic chip 10 is disposed between the electrodecontact terminal 28 and a closing end of the cover 29 when the cover 29is in a closed position.

Referring to the electrolytic chip loading stations 11 shown in FIGS. 5Cand 5D, the electrode contact terminal 28 and the spring pad 27 aredisposed under the cover 29, such that the electrode contact terminal 28is disposed between the cover 29 and the electrolytic chip 10 when thecover 29 is in a closed position. The electrolytic chip loading station11 shown in FIG. 5C is different from that shown in FIG. 5D with respectto the position of a pivot shaft of the cover 29.

As described above, the use of a spring pad, such as spring pad 27,ensures a strong contact between electrodes of an electrolytic chip 10and an electrode contact terminal 28 of an electrolytic chip loadingstation 11 and easy placement of the electrolytic chip 10 on theelectrolytic chip loading station 11.

Referring again to FIG. 1, according to an exemplary embodiment of thepresent invention, the input unit 12 for inputting electrolysisconditions, e.g., a current or voltage to be applied to the electrolyticchip 10, a current application time, or a voltage application time mayinclude a plurality of buttons, e.g. such as shown in FIGS. 6A and 6B.

For example, the input unit 12 may include a “down” button, an “up”button, and a “menu/start” button. As the “menu/start” button isrepeatedly pressed, the constant current setting menu, the constantvoltage setting menu, the time setting menu, and the electrolysis startmenu appear in sequence. In each menu, a user can select desired valuesby pressing the “down” button or the “up” button. While a three buttonsystem is described for the input unit 12, alternate input units 12would also be within the scope of these embodiments.

The display unit 14 for displaying the conditions and progress of theelectrolysis is not particularly limited, and may be a liquid crystaldisplay (“LCD”). For example, the input unit 12 may be combined with thedisplay unit 14 using a touch-screen display unit.

The control unit 13 receives the electrolysis conditions, such asinputted by the input unit 12, and controls electrolysis performed inthe electrolytic chip 10. The control unit 13 can also controlanalog-to-digital conversion, analog output, memory, buttons, thedisplay unit 14, inter-device communication, etc., in addition toelectrolysis.

The pH adjusting apparatus of the present invention may further includea voltage measurement unit 30 for measuring a voltage applied to theelectrolytic chip 10 and for transmitting the measured voltage to thecontrol unit 13. For example, the voltage measurement unit 30 mayinclude operational amplifiers (“OP-AMPs”) 32 a and 32 b. The controlunit 13 can apply a constant voltage to the electrolytic chip 10 basedon the voltage measured by the voltage measurement unit 30.

The pH adjusting apparatus of the present invention may further includea current measurement unit 31 for measuring a current applied to theelectrolytic chip 10 and transmitting the measured current to thecontrol unit 13. For example, the current measurement unit 31 mayinclude an OP-AMP 32 c and a resistor 33. The control unit 13 can applya constant current to the electrolytic chip 10 based on the currentmeasured by the current measurement unit 31.

The pH adjusting apparatus of the present invention may further includean interface 34 that can be connected to a peripheral computer (notshown). For example, the interface 34 may be an RS232 serial port.

The pH adjusting apparatus of the present invention may further includea memory device 35 for storing information. For example, the informationmay include set values, conversion factors, etc., and the memory device35 may be an electrically erasable programmable read-only memory(“EEPROM”).

The pH adjusting apparatus of the present invention may further includea power supply unit 36. In an exemplary embodiment of the presentinvention, the power supply unit 36 may be a battery, e.g., a 3.6 VLi-ion battery, although alternate power supply units would also bewithin the scope of these embodiments.

The pH adjusting apparatus of the present invention may further includean adaptor port 37 that can be connected to an external power (notshown).

The applied power is not particularly limited but may be 3˜12 V.

In an exemplary embodiment of the present invention, the pH adjustingapparatus of the present invention may further include a power controlunit 38 for converting the applied power, from an external source viathe adaptor port 37 or from the power supply unit 36, into differentpowers and supplying the different powers to the electrolytic chip 10,the control unit 13, and the display unit 14.

For example, the power control unit 38 can convert an applied power topredetermined voltages and then transmit a voltage of 16V to theelectrolytic chip 10, a voltage of 5V to a printed circuit board (“PCB”)including the control unit 13, and a voltage of 3.2 V to the displayunit 14.

FIG. 6A is a perspective view illustrating an exemplary embodiment of apH adjusting apparatus according to the present invention, FIG. 6B is afront view of the exemplary pH adjusting apparatus of FIG. 6A, FIG. 6Cis a top view of the exemplary pH adjusting apparatus of FIG. 6A, FIG.6D is a rear view of the exemplary pH adjusting apparatus of FIG. 6A,FIG. 6E is a front image of the exemplary pH adjusting apparatus of FIG.6A, and FIG. 6F is an image showing a state where an exemplaryelectrolytic chip loading station is uncovered.

Referring to FIGS. 6A through 6D, a pH adjusting apparatus of thepresent invention includes an LCD 14 used as a display unit, three inputbuttons 12 a, 12 b, and 12 c for the input unit 12, and an electrolyticchip loading station 11 on a front surface thereof, an interface 34, anadaptor port 37, and an “on/off” switch 39 on a top surface thereof, anda battery 36 used as a power supply unit on a rear surface thereof. ThepH adjusting apparatus also includes an upper case 40 and a lower case42. While a particular arrangement of the elements visible on theexterior of the pH adjusting apparatus is illustrated, it should beunderstood that alternate arrangements of the elements of the pHadjusting apparatus would also be within the scope of these embodiments.

Referring to FIG. 6E, an LCD 14 displays, for example, an electrolysisrunning time, an applied current, and an applied voltage. Referring toFIG. 6F, an electrolytic chip loading station 11 is uncovered. Here, theelectrolytic chip loading station 11 is as illustrated in FIG. 5A. ThepH adjusting apparatus shown in FIGS. 6E and 6F was manufactured to havedimensions of 6 cm in width, 4 cm in length, and 3 cm in height, thusrendering portability to the pH adjusting apparatus, although thedimensions are not limited thereto. For example, the pH adjustingapparatus can be sized to fit and be carried by an average adult humanhand.

FIG. 7A is an exploded perspective view illustrating an exemplaryembodiment of a pH adjusting apparatus according to the presentinvention, FIG. 7B is an image of a display unit of the exemplary pHadjusting apparatus of FIG. 7A, FIG. 7C is a front image of an exemplaryPCB of the exemplary pH adjusting apparatus of FIG. 7A, and FIG. 7D is arear image of the exemplary PCB of the exemplary pH adjusting apparatusof FIG. 7A.

Referring to FIG. 7A, a PCB 41 is shown to include the control unit 13,and may further support the input unit 12, the electrode contactterminal 28, the OP-AMP 32, the interface 34, the memory device 35, theadaptor port 37, and the on-off switch 39 thereon, for electricallyconnecting the elements. An exemplary embodiment of the PCB 41 is shownin detail in FIGS. 7C and 7D. The LCD 14, as further shown in FIG. 7B,may be positioned between the upper case 40 and the PCB 41. The uppercase 40 may include an opening for exposing a display region of the LCD14, and openings for accessing the buttons 12 a, 12 b, and 12 c of theinput unit 12. The upper case 40 may further include the electrolyticchip loading station 11 for receiving the electrolytic chip 10 therein.The PCB 41 may be positioned within the lower case 42 and may beelectrically connected to battery disposed on a rear surface of thelower case 42. The upper case 40 and lower case 42 may be connected toeach other to enclose the PCB 41 therein.

The present invention also provides an exemplary method of adjusting thepH of a solution in an easy and accurate manner using constant currentelectrolysis.

The pH adjusting method may include: (a) supplying a solution includingan ion having a lower or higher standard oxidation potential than waterinto an anode chamber of an electrolytic chip and supplying a solutionincluding an ion having a lower standard reduction potential than waterinto a cathode chamber of the electrolytic chip; (b) loading theelectrolytic chip on an electrolytic chip loading station; (c) inputtingelectrolysis conditions using an input part of a pH adjusting apparatus;and (d) performing electrolysis in the anode chamber and the cathodechamber by passing a current through an anode and a cathode of theelectrolytic chip according to the electrolysis conditions so that thesolution supplied into the anode chamber or the solution supplied intothe cathode chamber is adjusted to have a predetermined pH value.

In an embodiment of the present invention, for introduction into theanode chamber of the electrolytic chip, the ion having a lower standardoxidation potential than water may be at least one anion selected fromNO₃ ⁻, F⁻, SO₄ ²⁻, PO₄ ³⁻, and CO₃ ²⁻, and the ion having a higherstandard oxidation potential than water may be an electrolyte includinga Cl⁻ ion. However, the present invention is not limited to theseexamples. In a case where the solution supplied into the anode chamberis a compound having a lower standard oxidation potential than water,electrolysis of water using a pH adjusting apparatus according to anembodiment of the present invention in the anode chamber produces anoxygen gas and a H⁺ ion. At this time, the pH of the solution in theanode chamber is lowered due to the H⁺ ion. Meanwhile, as describedabove, in a case where the anode is made of a metal that has a higherstandard oxidation potential than water and does not react with water,no oxygen gas is generated due to the oxidation of the metal. The Cl⁻ion having a higher standard oxidation potential than water can be usedonly for the special purpose of cell lysis.

In an embodiment of the present invention, for introduction into thecathode chamber of the electrolytic chip, the ion having a lowerstandard reduction potential than water may be a cation such as Na⁺, K⁺,Ca²⁺, Mg²⁺, and Al³⁺, but the present invention is not limited to theseexamples. Thus, electrolysis of water using a pH adjusting apparatusaccording to the present invention in the cathode chamber produces ahydrogen gas and an OH⁻ ion. At this time, the pH of the solution in thecathode chamber is increased due to the OH⁻ ion. Meanwhile, as describedabove, in a case where the cathode is made of a metal capable ofadsorbing a hydrogen gas, the produced hydrogen gas is adsorbed by thecathode, thereby resulting in no generation of gas bubbles.

In an exemplary embodiment of the present invention, the solutionsupplied into the cathode chamber may include a cell or a virus, andcell or virus lysis may occur at the adjusted pH of the solution.

In another exemplary embodiment of the present invention, the solutionsupplied into the cathode chamber may be selected from a group includingsaliva, urine, blood, serum, and a cell culture.

In yet another exemplary embodiment of the present invention, theelectrolysis conditions may include a current or voltage applied to theelectrolytic chip, a current application time, or a voltage applicationtime.

In still another exemplary embodiment of the present invention, theelectrolysis conditions may include a constant current applied to theelectrolytic chip and a constant current application time.

FIG. 8A is a flow diagram illustrating an exemplary embodiment of aprogram executed in an exemplary control unit of an exemplary pHadjusting apparatus according to the present invention, FIG. 8B is aflow diagram illustrating an exemplary embodiment of menu/voltagecontrol, FIG. 8C is a flow diagram illustrating an exemplary embodimentof AD conversion/current control, and FIG. 8D is a flow diagramillustrating an exemplary embodiment of data communication with aperipheral computer via an interface.

Referring to FIG. 8A, when the control unit 13 is initialized, such asby turning the unit on using the on-off switch 39, the LCD 14 isinitialized and displays a start menu. Then, data values are read andthen set and calibrated. At this time, at least one of three interruptsmay occur. A 75 Hz interrupt may initiate the menu/voltage control asshown in FIG. 8B. A 256 Hz interrupt may initiate the ADconversion/current control as shown in FIG. 8C. A receiver interrupt mayinitiate the data communication with a peripheral computer via aninterface as shown in FIG. 8D.

Referring to FIG. 8B, together with FIGS. 6A through 6F illustrating apH adjusting apparatus including an input unit 12 having three buttons,as a button 1, such as button 12A, is repeatedly pressed, the currentsetting menu, the time setting menu, and the voltage setting menu appearin sequence. In each menu, when a button 2 (“up” button), such as button12B, or a button 3 (“down” button), such as button 12C, is pressed, acurrent, a time, and a voltage can be adjusted to desired values. Inparticular, a set value (such as current, time, or voltage) can beincreased by pressing the button 2, and the set value can be decreasedby pressing the button 3.

For example, the button 1 can be pressed three times to display thevoltage setting menu, the voltage can be adjusted to a desired valueusing the button 2 or 3, such as by increasing a set voltage if thebutton 2 is pressed or decreasing a set voltage if the button 3 ispressed, and then the button 1 can be pressed again to startelectrolysis. Therefore, a constant voltage can be applied to anelectrolytic chip by a voltage measurement unit and a control unit toperform electrolysis.

Referring to FIG. 8C, together with FIG. 8B, the button 1 is pressedonce to set the constant current, the button 1 is pressed again to setthe electrolysis time, and the button 1 is pressed again to startelectrolysis. At this time, a current measurement unit, such as currentmeasurement unit 31 shown in FIG. 1, and a control unit 13 according tothe present invention constantly maintain the current applied to anelectrolytic chip. Because the current measurement unit 31 measures acurrent applied to the electrolytic chip 10 and transmits the measuredcurrent to the control unit 13, the control unit 13 can then apply aconstant current to the electrolytic chip 10 based on the currentmeasured by the current measurement unit 31. Thus, a continuous loop isfollowed, and the AD conversion and current control shown in FIG. 8Ccontinues until a set time is reached, such as when the electrolysisprocedure is programmed to stop.

Current is the most important factor in pH adjustment usingelectrolysis. The pH adjusting apparatus according to exemplaryembodiments of the present invention can accurately control current, inparticular a constant current, and thus, the pH of a solution can beadjusted easily and accurately.

Referring to FIG. 8D, a receiver interrupt may initiate datacommunication with a peripheral computer via an interface, such asinterface 34. For example, the data decoding may result in a startcommand, a stop command, a set value change command, a calibration valuechange command, a memory writing command, etc. That is, the peripheralcomputer may serve as an input unit for the control unit 13, and mayfurther direct operations of the control unit 13.

According to the pH adjusting apparatus and method of the presentinvention, the pH of a solution can be adjusted easily and accurately,regardless of a gas generated during electrolysis, a salt concentrationin a sample, or a cytosolic salt concentration variation during celllysis, by precisely controlling a constant current, a constant voltage,and current and voltage application times, in particular the constantcurrent, thereby enabling useful application of the pH adjustingapparatus and method of the present invention in various biologicalassays such as cell lysis. Furthermore, the pH adjusting apparatus ofthe present invention is easy to carry due to small size and weight andcan be operated for a long time after charging once due to low powerconsumption (e.g., working time of about 7 hours based on 3.7V batteryand 650 mAh).

Hereinafter, the present invention will be described more specificallywith reference to the following working examples. The following workingexamples are for illustrative purposes and are not intended to limit thescope of the invention.

EXAMPLE 1

pH Adjustment Experiments Using Exemplary Embodiment Of pH AdjustingApparatus According to the Present Invention

A pH adjusting apparatus as shown in FIGS. 6A through 6F was used andthe pH adjusting capability of the apparatus was evaluated.

For this, 10 μl of a 55 mM Na₂SO₄ solution was supplied into each of acathode chamber and an anode chamber of an electrolytic chip, and theelectrolytic chip was loaded on an electrolytic chip loading station.Then, electrolysis was performed by varying the settings of a constantcurrent and a current running time, and the pH of the solution in eachof the cathode chamber and the anode chamber was measured.

The results are presented in Table 1 below. As shown in Table 1, it canbe seen that the use of a pH adjusting apparatus of the presentinvention enables easy and accurate adjustment of the pH of a solution.

TABLE 1 1 mA 2 mA 3 mA 4 mA Time Anode Cathode Anode Cathode AnodeCathode Anode Cathode (sec) chamber chamber chamber chamber chamberchamber chamber chamber 3 2 12 1 13 1 13 0 14 6 1 13 1 13 0 14 0 14 9 113 0 14 0 14 0 14 12 1 13 0 14 0 14 0 14 15 0 14 0 14 0 14 0 14

While the present invention has been particularly shown and describedwith reference to exemplary embodiments thereof, it will be understoodby those of ordinary skill in the art that various changes in form anddetails may be made therein without departing from the essentialfeatures of the present invention. Thus, the embodiments of the presentinvention described above are to be deemed in all respects as beingmerely illustrative and not restrictive. The scope of the presentinvention is defined by the appended claims, not the above description,and it should be understood that all the equivalents fall within thescope of the appended claims.

1. A pH adjusting apparatus comprising: an electrolytic chip which receives a solution whose pH is to be adjusted, the electrolytic chip comprising: an enclosed chamber including a cathode at a side of the chamber and an anode at an opposite side of the chamber, and in which the pH of the solution is adjusted; an ion-exchange material which divides the enclosed chamber into a cathode chamber comprising the cathode and an anode chamber comprising the anode; and an anode support between the anode and the ion-exchange material; an electrolytic chip loading station that receives the electrolytic chip; an input unit that inputs electrolysis conditions; a control unit which receives the electrolysis conditions from the input unit and controls electrolysis in the electrolytic chip, a current measurement unit which measures a current applied to the electrolytic chip and transmits the measured current to the control unit, wherein the control unit applies a constant current to the chamber of the electrolytic chip based on the current measured by the current measurement unit; and a display unit that displays the electrolysis conditions and a progress of the electrolysis.
 2. The pH adjusting apparatus of claim 1, wherein the electrolytic chip loading station comprises: an electrolytic chip support which supports the electrolytic chip; an electrode contact terminal which contacts the cathode and the anode of the electrolytic chip and comprises a spring pad; and a cover which covers the electrolytic chip when the electrolytic chip is loaded on the electrolytic chip support.
 3. The pH adjusting apparatus of claim 2, wherein the electrode contact terminal is formed on an inside of the cover.
 4. The pH adjusting apparatus of claim 2, wherein the electrode contact terminal is formed on the electrolytic chip support.
 5. The pH adjusting apparatus of claim 1, wherein the electrolysis conditions comprise the constant current applied to the electrolytic chip, a voltage applied to the electrolytic chip, a current application time, or a voltage application time.
 6. The pH adjusting apparatus of claim 5, wherein the electrolysis conditions comprise a constant current application time.
 7. The pH adjusting apparatus of claim 1, further comprising a voltage measurement unit that measures a voltage applied to the electrolytic chip and transmits measured voltage to the control unit.
 8. The pH adjusting apparatus of claim 1, further comprising an interface connected to a peripheral computer.
 9. The pH adjusting apparatus of claim 1, further comprising a memory device which stores information.
 10. The pH adjusting apparatus of claim 1, further comprising a power supply unit.
 11. The pH adjusting apparatus of claim 1, further comprising a power control unit which converts an applied power to different powers and supplies the different powers to the electrolytic chip, the control unit, and the display unit.
 12. The pH adjusting apparatus of claim 1, wherein the input part includes a first button, a second button, and a third button, and pressing the first button selects between a current setting menu, a time setting menu, and a voltage setting menu, pressing the second button increases a value of current, time, or voltage, and pressing the third button decreases a value of current, time, or voltage.
 13. The pH adjusting apparatus of claim 1, wherein the pH adjusting apparatus is sized to fit within an average adult human hand.
 14. A pH adjusting apparatus comprising: a contact terminal which contacts an electrolytic chip receiving a solution whose pH is to be adjusted, the electrolytic chip including an enclosed chamber in which the pH of the solution is adjusted and including: a cathode at a side of the chamber; an anode at an opposite side of the chamber; an ion-exchange material dividing the chamber into a cathode chamber comprising the cathode and an anode chamber comprising the anode; and an anode support between the anode and the ion-exchange material a control unit which controls electrolysis in the electrolytic chip; and a current measurement unit which measures a current applied to the electrolytic chip and transmits the measured current to the control unit, wherein the control unit applies a constant current to the chamber of the electrolytic chip based on the current measured by the current measurement unit; wherein the cathode and the anode of the electrolytic chip contact the contact terminal of the pH adjusting apparatus and receive the constant current through the contact terminal such that the pH of the solution is adjusted.
 15. The pH adjusting apparatus of claim 14, wherein the anode is ladder-shaped and the ion-exchange material is an ion-exchange membrane.
 16. The pH adjusting apparatus of claim 14, further comprising a pillar structure between the cathode and the ion-exchange material, wherein the anode support and the pillar structure support the ion-exchange material there between.
 17. The pH adjusting apparatus of claim 1, further comprising a pillar structure between the cathode and the ion-exchange material, wherein the anode support and the pillar structure support the ion-exchange material there between. 